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DTC P0134: A/F/O2 Sensor Circuit No Activity Detected Bank 1 Sensor 1: Notes

DTC detecting condition: 

Immediately at fault recognition

CAUTION:
  • After servicing or replacing faulty parts, perform Clear Memory Mode Ref. to OPERATION , Clear Memory Mode, and Inspection Mode Ref. to PROCEDURE , Inspection Mode.
  • Use the check board when measuring the ECM terminal voltage and resistance.

Wiring diagram: 

Engine Electrical System Ref. to WIRING DIAGRAM , Engine Electrical System.

Fig 1: A/F And O2 Sensor Circuit No Activity Detected Bank 1 Sensor 1 - Wiring Diagram
G11583295Courtesy of SUBARU OF AMERICA, INC.
Step Check Yes No
1 CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connector from ECM.
  3. Disconnect the connectors from front oxygen (A/F) sensor.
  4. Measure the resistance of harness between ECM connector and front oxygen (A/F) sensor connector.

Connector & terminal 
(E158) No. 46 - (E24) No. 3: 
(E158) No. 33 - (E24) No. 4: 
Is the resistance less than 1 Ω? Go to step Repair the open circuit of harness between ECM connector and front oxygen (A/F) sensor connector.
2 CHECK FOR POOR CONTACT. 
Check for poor contact of ECM and front oxygen (A/F) sensor connector.
Is there poor contact of ECM or front oxygen (A/F) sensor connector? Repair the poor contact of ECM or front oxygen (A/F) sensor connector. Replace the front oxygen (A/F) sensor. Ref. to FRONT OXYGEN (A/F) SENSOR